Fenestration closure with Amplatzer Duct Occluder II in patients after total cavo-pulmonary connection

INTRODUCTION

Creation of a fenestration during completion of a total cavopulmonary connection (TCPC) has been associated with a reduction in early mortality and morbidity. However, the long-term benefits are negated by an associated limitation in exercise tolerance and the potential risks of thrombo-embolic complications. We sought to describe the safety and efficacy of an Amplatzer Duct Occluder II (ADO II) for transcatheter fenestration closure following TCPC.

MATERIAL AND METHODS

Between January 2000 and July 2014, 102 patients underwent percutaneous closure of extra-cardiac TCPC fenestrations with a range of devices. Patients in whom fenestration closure was performed with an ADO II and who had at least 6 months of follow-up were included in this study.

RESULTS

Forty-seven patients had successful fenestration occlusion with an ADO II. The mean oxygen saturation and mean systemic venous pressures increased from 84.8 ±6.1% before to 97.6 ±2.9% (p < 0.001) after and from 14.2 ±2.15 mm Hg before to 15.6 ±2.2 mm Hg after closure (p < 0.001). Eight patients developed heart failure symptoms, managed by optimization of medical therapy, with 1 patient requiring device removal to reopen the fenestration. Color Doppler transthoracic echocardiography demonstrated residual flow across the device in 18 (38%), 10 (22%), 5 (11%) and 4 (9%) patients before discharge, at 1 and 6 months, and at the latest outpatient visit, respectively.

CONCLUSIONS

The ADO II can be safely and effectively used to close fenestrations in extra-cardiac type Fontan completions. Many of the design features of this device confer potential benefit in this population.

Restricting feeding to the active phase in middle-aged mice attenuates adverse metabolic effects of a high-fat diet

Time-restricted feeding ameliorates the deleterious effects of a high-fat diet on body weight and metabolism in young adult mice. Because obesity is highly prevalent in the middle-aged population, this study tested the hypothesis that time-restricted feeding alleviates the adverse effects of a high-fat diet in male middle-aged (12months) mice. C57BL6/J mice were fed one of three diets for 21-25weeks: 1) high-fat diet (60% total calories from fat) ad-libitum (HFD-AL), 2) HFD, time-restricted feeding (HFD-TRF), and 3) low-fat diet (10% total calories from fat) ad-libitum (LFD-AL) (n=15 each). HFD-TRF mice only had food access for 8h/day during their active period. HFD-TRF mice gained significantly less weight than HFD-AL mice (~20% vs 55% of initial weight, respectively). Caloric intake differed between these groups only during the first 8weeks and accounted for most but not all of their body weight difference during this time. TRF of a HFD lowered glucose tolerance in terms of incremental area under the curve (iAUC) (p<0.02) to that of LFD-AL mice. TRF of a HFD lowered liver weight (p<0.0001), but not retroperitoneal or epididymal fat pad weight, to that of LFD-AL mice. Neither HFD-AL nor HFD-TRF had any effect on performance in the novel object recognition or object location memory tests. Circulating corticosterone levels either before or after restraint stress were not affected by diet. In conclusion, TRF without caloric restriction is an effective strategy in middle-aged mice for alleviating the negative effects of a HFD on body weight, liver weight, and glucose tolerance.

Extended interval dosing of natalizumab in multiple sclerosis

BACKGROUND

Natalizumab (NTZ), a monoclonal antibody to human α4β1/β7 integrin, is an effective therapy for multiple sclerosis (MS), albeit associated with progressive multifocal leukoencephalopathy (PML). Clinicians have been extending the dose of infusions with a hypothesis of reducing PML risk. The aim of the study is to evaluate the clinical consequences of reducing NTZ frequency of infusion up to 8 weeks 5 days.

METHODS

A retrospective chart review in 9 MS centres was performed in order to identify patients treated with extended interval dosing (EID) regimens of NTZ. Patients were stratified into 3 groups based on EID NTZ treatment schedule in individual centres: early extended dosing (EED; n=249) every 4 weeks 3 days to 6 weeks 6 days; late extended dosing (LED; n=274) every 7 weeks to 8 weeks 5 days; variable extended dosing (n=382) alternating between EED and LED. These groups were compared with patients on standard interval dosing (SID; n=1093) every 4 weeks.

RESULTS

17% of patients on SID had new T2 lesions compared with 14% in EID (p=0.02); 7% of patients had enhancing T1 lesions in SID compared with 9% in EID (p=0.08); annualised relapse rate was 0.14 in the SID group, and 0.09 in the EID group. No evidence of clinical or radiographic disease activity was observed in 62% of SID and 61% of EID patients (p=0.83). No cases of PML were observed in EID group compared with 4 cases in SID cohort.

CONCLUSIONS

Dosing intervals up to 8 weeks 5 days did not diminish effectiveness of NTZ therapy. Further monitoring is ongoing to evaluate if the risk of PML is reduced in patients on EID.

Expert consensus statement 'Neonatologist-performed Echocardiography (NoPE)'-training and accreditation in UK

Targeted echocardiographic assessments of haemodynamic status are increasingly utilised in many settings. Application in the neonatal intensive care units (NICU) is increasingly demanded but challenging given the risk of underlying structural lesions. This statement follows discussions in UK led by the Neonatologists with an Interest in Cardiology and Haemodynamics (NICHe) group in collaboration with the British Congenital Cardiac Association (BCCA) and the Paediatricians with Expertise in Cardiology Special Interest Group (PECSIG). Clear consensus was agreed on multiple aspects of best practice for neonatologist-performed echocardiogram (NoPE)-rigorous attention to infection control and cardiorespiratory/thermal stability, early referral to paediatric cardiology with suspicion of structural disease, reporting on standardised templates, reliable image storage, regular skills maintenance, collaboration with a designated paediatric cardiologist, and regular scan audit/review. It was agreed that NoPE assessments should confidently exclude structural lesions at first scan. Practitioners would be expected to screen and establish gross normality of structure at first scan and obtain confirmation from paediatric cardiologist if required, and subsequently, functional echocardiography can be performed for haemodynamic assessment to guide management of newborn babies. To achieve training, NICHe group suggested that mandatory placements could be undertaken during core registrar training or neonatal subspecialty grid training with a paediatric cardiology placement for 6 months and a neonatology placement for a minimum of 6 months. In the future, we hope to define a precise curriculum for assessments. Technological advances may provide solutions-improvements in telemedicine may have neonatologists assessing haemodynamic status with paediatric cardiologists excluding structural lesions and neonatal echocardiography simulators could increase exposure to multiple pathologies and allow limitless practice in image acquisition.

CONCLUSION

We propose developing training places in specialist paediatric cardiology centres and neonatal units to facilitate training and suggest all UK practitioners performing neonatologist-performed echocardiogram adopt this current best practice statement.

WHAT IS KNOWN

Neonatologist-performed echocardiogram (NoPE) also known as targeted neonatal echocardiography (TNE) or functional ECHO is increasingly recognised and utilised in care of sick newborn and premature babies. There are differences in training for echocardiography across continents and formal accreditation processes are lacking.

WHAT IS NEW

This is the first document of consensus best practice statement for training of neonatologists in neonatologist-performed echocardiogram (NoPE), jointly drafted by Neonatologists with interest in cardiology & haemodynamics (NICHe), paediatric cardiology and paediatricians with expertise in cardiology interest groups in UK. Key elements of a code of practice for neonatologist-performed echocardiogram are suggested.

Anesthetic management of a patient with Weaver syndrome undergoing emergency evacuation of extra-dural hematoma: A case report and review of the literature

Weaver syndrome is a rare disorder of unknown etiology characterized by skeletal overgrowth, distinctive craniofacial and digital abnormalities and advanced bone age. In general, craniofacial abnormalities that cause difficulty with tracheal intubation may improve, worsen, or remain unchanged as craniofacial structures mature. Furthermore, there is an estimated risk in these children of ≤1.09% of rhabdomyolysis or malignant hyperpyrexia. We report a case of a boy with Weaver syndrome who underwent emergency evacuation of extra-dural hematoma under general anesthesia.

Evaluating a murine model of endometritis using uterine isolates of Escherichia coli from postpartum buffalo

Ascending infection of the uterus with Gram-negative bacteria is responsible for postpartum endometritis in cattle and buffalo and can adversely affect fertility. Development of a laboratory animal model for bovine endometritis would facilitate the understanding of the pathogenesis as it is difficult to conduct controlled experimentation in the native host. In the present study, 30 virgin Swiss Albino mice (5-8 weeks old) were used to evaluate the pathogenic potential of Escherichia coli, isolated from the normally calved postpartum buffalo to induce endometritis. Mice in the diestrus phase of the estrous cycle were randomly allotted to one of the following four intravaginal inoculation (100 μL) treatments: EG (experimental group)-1: sterile normal saline; EG-2, -3 and -4: E. coli^@ 1.5 × 10⁴, 10⁵ and 10⁶ CFU/ml, respectively. The animals were then scarified 36 h post-inoculation to study gross and microscopical lesions. Gross changes were confined to EG-4. Acute endometritis was recorded in 50% of the EG-3 and 66.7% of the EG-4. The rate of acute endometritis development was significantly higher in EG-4 (P<0.05) as compared to the other groups. The present study demonstrated that the animal model for bubaline endometritis can be developed in mice by intravaginal inoculation of E.coli^@ 1.5 × 10⁶ CFU/ml at diestrus. Ease of intravaginal inoculation, apparent absence of systemic involvement and high infective rate are the advantages of the model over other studies.

Superbugs causing ventilator associated pneumonia in a tertiary care hospital and the return of pre-antibiotic era!

The rise in super bugs causing Ventilator-Associated Pneumonia (VAP) is a major cause of mortality and morbidity despite recent advances in management owing to the looming 'antibiotic apocalypse'. The aetiology and susceptibility pattern of the VAP isolates varies with patient population, type of intensive care unit (ICU) and is an urgent diagnostic challenge. The present study carried out for a period of one year in a tertiary care hospital, enrolled patients on mechanical ventilation (MV) for ≥48 hrs. Endotracheal aspirates (ETA) from suspected VAP patients were processed by semi quantitative method. Staphylococus aureus, members of Enterobacteriaceae were more common in early onset VAP (EOVAP), while Nonfermenting Gram negative bacilli (NFGNB) were significantly associated with late onset VAP (LOVAP). Most of the isolates were multi drug resistant (MDR) super bugs. With limited treatment options left for this crisis situation like the pre-antibiotic era; it is an alarm for rational antibiotic therapy usage and intensive education programs.

MPLA shows attenuated pro-inflammatory properties and diminished capacity to activate mast cells in comparison with LPS

BACKGROUND

Monophosphoryl lipid A (MPLA), a nontoxic TLR4 ligand derived from lipopolysaccharide (LPS), is used clinically as an adjuvant in cancer, hepatitis, and malaria vaccines and in allergen-specific immunotherapy. Nevertheless, its cell-activating effects have not been analyzed in a comprehensive direct comparison including a wide range of different immune cells. Therefore, the objective of this study was the side-by-side comparison of the immune-modulating properties of MPLA and LPS on different immune cells.

METHODS

Immune-activating properties of MPLA and LPS were compared in human monocytes and mast cells (MCs), a mouse endotoxin shock model (ESM), and mouse bone marrow (BM)-derived myeloid dendritic cells (mDCs), T cells (TCs), B cells, and MCs.

RESULTS

In a mouse in vivo ESM and a human ex vivo monocyte activation test (MAT), MPLA induced the same cytokine secretion pattern as LPS (ESM: IL-6, IL-12, TNF-α; MAT: IL-1β, IL-6, TNF-α), albeit at lower levels. Mouse mDCs and ex vivo isolated B cells stimulated with MPLA required a higher threshold to induce TRIF-dependent cytokine secretion (IL-1β, IL-6, IL-10, and TNF-α) than did LPS-stimulated cells. In mDC:DO11.10 CD4 TC cocultures, stimulation with MPLA, but not with LPS, resulted in enhanced OVA-specific IL-4 and IL-5 secretion from DO11.10 CD4 TCs. Unexpectedly, in both human and mouse MCs, MPLA, unlike LPS, did not elicit secretion of pro-inflammatory cytokines.

CONCLUSIONS

Compared to LPS, MPLA induced a qualitatively similar, but less potent pro-inflammatory immune response, but was unable to activate human or mouse MCs.

Middle aortic syndrome--an 8-year story of pills, pretty balloons and struts

BACKGROUND

Middle aortic syndrome (MAS) is an uncommon cause of hypertension in children. The management of hypertension secondary to MAS frequently requires several anti-hypertensive medications along with endovascular and often surgical intervention.

CASE-DIAGNOSIS/TREATMENT

A 9-year-old boy presented with headaches and vomiting and was diagnosed with severe hypertension secondary to idiopathic MAS affecting a long segment of the abdominal aorta and left renal artery stenosis. Over the following 8 years his hypertension was successfully managed initially with percutaneous transluminal balloon angioplasty (PTA) of his left renal artery, followed by balloon dilatation of his abdominal aortic narrowing. He subsequently underwent abdominal aortic stent placement following failed repeat aortic balloon dilatation. Aged 17 years and 6 months he is now on a single anti-hypertensive agent with normal renal function and no evidence of target organ damage.

CONCLUSION

In selected cases, MAS may be managed with PTA and stent placement with good long-term outcomes. Limited data on the use of PTA and stent insertion in children means that a structured approach to the management of refractory hypertension secondary to MAS remains elusive.

Central aortic blood pressure from ultrasound wall-tracking of the carotid artery in children: comparison with invasive measurements and radial tonometry

Differences between central aortic root (c) and peripheral (p) systolic blood pressure (SBP) may be particularly marked in children, but noninvasive methods for assessing cSBP in children have not been validated. We compared estimates of cSBP obtained from radiofrequency ultrasound wall tracking of the carotid artery (ART.LAB system) with that measured directly by a catheter in the aortic root at the time of arterial cannulation. Carotid waveforms were calibrated from invasive measurements of mean and diastolic pressures. In 9 children aged 10.5 ± 5.0 years (mean ± SD), cSBP obtained from carotid wall tracking was highly correlated with invasive measures of cSBP (r=0.99) with mean (± SD) difference 3.9 ± 2.5 mm Hg. Second, we compared values of cSBP obtained from the carotid with those obtained using noninvasive applanation tonometry at the radial artery and a radial-to-aortic transfer function (SphygmoCor). Both carotid and radial tonometric measurements were calibrated from the same peripheral mean and diastolic measurements of blood pressure obtained by sphygmomanometry. In 84 children aged 13.2 ± 3.2 years, there was excellent agreement between the 2 methods (r=0.95; P<0.001) with mean difference 0.71 ± 3.7 mm Hg (95% confidence interval =-1.53 to 1.01). This invasive validation study confirms that cSBP as estimated by carotid wall tracking provides an acceptable measurement of true cSBP when calibration is from true mean and diastolic pressures. Close agreement of cSBP obtained by carotid wall tracking and radial tonometry suggests that these provide similar results when calibrated from the same peripheral blood pressure measurements.

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-making.

Mixed pulmonary infection in an immunocompromised patient: a rare case report

Patients who are immunocompromised are predisposed to a variety of common and uncommon pulmonary infections. We report a case of mixed pulmonary infection by drug resistant tuberculosis with a nocardiosis in a 49-year-old man who was a known case of chronic obstructive pulmonary disease, on prolonged corticosteroid use with diabetes mellitus. Chronic use of corticosteroids is a predisposing factor for opportunistic infections, such as nocardiosis or tuberculosis. Since such a mixed infection is rare, maybe a combined approach to therapy early in the course of disease would be effective in such cases.

Transcatheter trans-septal antegrade closure of muscular ventricular septal defects in young children

BACKGROUND

Surgical or transcatheter closure of muscular ventricular septal defects (mVSDs) in young children may be technically challenging and associated with significant complications.

OBJECTIVE

To assess the feasibility of trans-septal antegrade closure of mVSD in a selected subset of young children.

METHODS

This is a prospective study from a single centre from July 2011 to March 2013. Nine infants and children with single or multiple mVSDs were included in the study. The median age and weight were 6 months (range 4-18 months) and 4.5 kg (range 3.8-6.2 kg), respectively. Trans-femoral trans-septal antegrade technique was used in eight children. One child was excluded from the study because of abnormally tortuous anatomy of both the femoral veins and subsequently underwent VSD device closure by the trans-jugular approach. The follow-up evaluation included chest X-ray, ECG, and echocardiogram at 1 month, 3 months, 6 months, and 1 year.

RESULTS

The defects were closed successfully in all eight patients using Amplatzer mVSD device in 5 and Amplatzer Duct Occluder II in 3. Moderate mitral regurgitation due to entrapment of the anterior mitral leaflet occurred in one patient with a posteriorly located mVSD, necessitating removal of the device, and surgical closure of the mVSD. The small additional residual mVSD in one other patient closed spontaneously during the follow-up.

CONCLUSIONS

Transcatheter trans-septal antegrade closure of mVSD in young children is technically feasible and merits further consideration. Symptomatic relief in multiple mVSD can be achieved after closing larger defects.

Iatrogenic aortopulmonary window after balloon dilation of left pulmonary artery stenosis following arterial switch operation

Branch pulmonary artery stenosis may occur in 4%-28% of patients after an arterial switch operation. Balloon dilation can be attempted with variable results, while stenting is a more definitive option when balloon dilation fails. We report the case of a young boy who underwent balloon dilation of a stenosed left pulmonary artery 9 years after an arterial switch operation and was noted to have an aortopulmonary window about a year later. This was treated with covered stent implantation, which dealt both with the aortopulmonary window and the residual stenosis. The diagnostic process with cardiac magnetic resonance imaging and cardiac catheterization of such an unusual entity as well as the transcatheter management are discussed in detail.

Highlights of the 6th World Congress in Paediatric Cardiology and Cardiac Surgery

The 6th World Congress in Paediatric Cardiology and Cardiac Surgery took place in Cape Town, South Africa, in February 2013. The congress is the largest meeting in the field of congenital and paediatric heart disease and attracts a global audience of specialists with the aim of sharing the latest multidisciplinary developments in research and clinical practice. The congress was commended as a huge success and this article aims to give a general flavor of the diverse meeting through detailing a few specific highlights from the various tracks.

Cardiovascular magnetic resonance imaging in congenital heart disease as an alternative to diagnostic invasive cardiac catheterization: a single center experience

OBJECTIVE

The study aims to assess whether the increasing use of cardiovascular magnetic resonance imaging in place of diagnostic cardiac catheterization in the management of pediatric patients with congenital heart disease has had an impact on pediatric cardiac care.

DESIGN

Retrospective analysis of data was used.

SETTING

The study was performed at the Evelina Children's Hospital Cardiology Department. PATIENTS. : Elective diagnostic cardiac catheterization or magnetic resonance imaging (MRI) from 2005-2010 are included (n = 896).

OUTCOME MEASURES

Indication, length of stay, and incidence of complications were recorded. In cases used to plan surgery, 30-day survival following the procedure was recorded. Surgical outcomes were compared between the two groups. Surgical outcomes planned using MRI were compared with national outcomes from Congenital Cardiac Audit Database.

RESULTS

For catheterizations (50 patients, [31 male, median age 3 years, interquartile range 1 to 12]), median hospital stay was 1 day (interquartile range 0 to 3), and complications occurred in 11 (22%). Median hospital stay for MRI (846 patients [517 male, median age 3 years, interquartile range 0 to 9]) was significantly shorter: 0 days (interquartile range 0 to 1, P <.001), with fewer complications (16 [1.9%], P <.0001). Twenty-four catheter and 283 MRI patients underwent surgery within 18 months. One catheter patient (2.0%) and four MRI patients (1.4%) died within 30 days (P =.48).

CONCLUSION

Replacing catheterization with cardiovascular magnetic resonance imaging has resulted in reduced rates of complication and shorter hospital stays without a significant impact on surgical outcome.

Retinal vascular changes following intravitreal ranibizumab injections for neovascular AMD over a 1-year period

PURPOSE

To assess retinal vascular calibre changes in eyes with neovascular age-related macular degeneration (AMD), treated with intravitreal anti-vascular endothelial growth factor agents, over a 1-year period and compare any such changes to untreated fellow eyes.

METHODS

Treatment naïve patients with neovascular AMD received three consecutive intravitreal injections of ranibizumab, followed by a pro re nata dosing regimen up to 1 year, with the aim of maintaining a 'fluid-free' macula. Retinal arteriolar and venular calibre was measured from digital fundus photographs at baseline and at three monthly intervals to 1 year, and summarised as central retinal artery equivalent (CRAE) and central retinal venular equivalent (CRVE), respectively.

RESULTS

A total of 53 injected eyes and 41 fellow, non-injected eyes were analysed. At baseline, there were no differences in retinal vascular calibre between injected and non-injected eyes (mean CRAE (SD) 144.93 (14.07) vs 145.74 (13.10) μm, P=0.80 and mean CRVE (SD) 216.23 (25.93) vs 219.91 (22.82) μm, P=0.53). Over a 12-month period, retinal venular calibre dilatation occurred in injected eyes (mean CRVE change +5.71 (14.71) μm, P=0.007), with no change in retinal arterioles, +0.69 (14.71) μm, P=0.68. In non-injected eyes, arteriolar narrowing occurred as a whole, mean CRAE change -4.20 (7.00) μm, P=0.001, over 12 months, with a trend for narrowing in venules, -2.16 (11.56) μm, P=0.28. In injected eyes, after controlling for covariates, the changes in CRVE over 12 months mirrored improvements in macular thickness, -0.06 (-0.005, -0.11) μm, P=0.04, and visual acuity, +9.66 (-0.30, +19.32) μm, P=0.06.

CONCLUSION

Intravitreal ranibizumab significantly dilated retinal venules after a 1-year period.

Measurements of 1/f Noise in A-Si:H Pin Diodes and Thin-Film-Transistors

We measured the equivalent noise charge of a-Si:H pin diodes (5 ∼ 45 μm i-layer) with a pulse shaping time of 2.5 μ.sec under reverse biases up to 30 V/μm and analyzed it as a four component noise source. The frequency spectra of 1/f noise in the soft-breakdown region and of the Nyquist noise from contact resistance of diodes were measured. Using the conversion equations for a CR-RC shaper, we identified the contact resistance noise and the 1/f noise as the main noise sources in the low bias and high bias regions respectively. The 1/f noise of a-Si:H TFTs with channel length of 15 μm was measured to be the dominant component up to ∼100kHz for both saturation and linear regions.

The Application of Thick Hydrogenated Amorphous Silicon Layers to Charged Particle and X-Ray Detection

We outline the characteristics of thick hydrogdenated amorphous silicon layers which are optimized for the detection of charged particles, x-rays and γ-rays. Signal amplitude as a function of the linear energy transfer of various particles are given. Noise sources generated by the detector material and by the thin film electronics - a-Si:H or polysilicon proposed for pixel position sensitive detectors readout are described, and their relative amplitudes are calculated. Temperature and neutron radiation effects on leakage currents and the corresponding noise changes are presented.